Process and machine for converting textile filaments



Nov. 6, 1951 N. E. KLIEIN I 2,573,717

PROCESS AND MACHINE FOR CONVERTING TEXTILE FILAMENTS Filed May 17; 1947. V

' mvzu-ron NORMN E. KLEIN ATTOR Patented Nov. 6, 1951 PROCESS AND MACHINE FOR CONVERTING TEXTILE FILAMENTS Norman E. Klein, Clemson, S. C., assignor to Deering Milliken Research Trust, New York, N. Y., a non-profit trust of New York Application May 17, 1947, Serial No. 748,803

The present invention relates to the production of yarn from relatively long or continuous fibers and comprises a novel method and apparatus particularly adapted for the direct production of relatively fine yarns from a tow of artificial filaments.

For the past seventy-five years the textile art has appreciated that slivers of long fibers, such as flax, hemp and the like, can be formed into rovings or yarns containing fibers of staple length by subjecting the sliver to tension between sets of draft rollers operating at successively increasing speed to break the individual fibers into staple lengths. In this manner, a continuous sliver of such fibers in staple length no greater than the ratch length is produced, Upon the introduction of artificial fibers in continuous filaments, the textile art, of course, applied the same method to the formation of rovings and yarns of these fibers in staple lengths from tows or slivers containing a multiplicity of these continuous filaments and, as expected, with some success.

In such direct conversion of tow to relatively fine yarns, however, difiiculties have been experienced with breaking of the yarn in or near the nips of the draft rolls with consequent interruption of the spinning process. There are various reasons why such excessive breakage occurs when fine yarn is being spun. The proce s is a combination of "slip draft and break draft.

That is, continuous filaments are being stretch broken in the ratch into fibers of staple length and at the same time these fibers are being drafted by relative slippage as in a straight drafting mechanism. Uneven distribution of interfiber friction due to changes in grouping of those filaments under-going stretch breaking result in uneven slip drafting with consequent thin or weak sections in the produced yarn. The yarn is apt to break at these weak or thin sections under the variable tension introduced by the builder motion of the traveller ring spindle assembly. Even without breakage the resulting yarn is nonuniform in cross-section and hence unsatisfactory for some purposes.

A general object of the invention is, therefore, to provide an improved process for the direct conversion of continuous filaments into yarn.

Further and more specific objects of the invention are to provide a method of, and means for, reducing excess breakage at or near the draft rolls in a direct tow to yarn spinner.

Still other objects of the invention are to provide a method of, and means for, converting a tow 4 Claims. (Cl. 57-2) 2 of artificial continuous filaments into substantially uniform and relatively fine yarn.

In accordance with the invention, these and other objects of the invention are obtained by introducing a slight twist into the sliver in the ratch preferably just above the draft rolls, which twist is in the same direction as that introduced into the yarn by the spinning operation. Twisting of the sliver increases the strength at emergence from the draft rolls and reduces breakage due to variable tension at that point Such twisting of the sliver in the ratch also gives a more uniform inter-fiber friction and thus stabilizes the "slip draft and further strengthens the resultant yarn and improves the uniformity thereof.

Other advantageous results flowing from the application of twist to the sliver'in the ratch, which includes improved blending of multiple ends of tow, and improved control of the drafting operation, will become apparent as the description proceeds.

In accordance with the invention, twist is introduced into the sliver in the ratch by a relative rotation between the draft and feed roll assemblies. In the preferred embodiment of the invention the feed roll a sembly is rotated about an axis perpendicular to the plane containing the axes of the rolls thereof.

Of the accompanying drawings:

Fig. 1 is a side view, partly in section of a direct tow to yarn spinning mechanism embodying the invention, and

Fig. 2 is a view similar to Fig. 1 but representing a modification.

In the embodiment of the invention illustrated in Fig. 1 the feed rolls of a direct tow to yarn spinning mechanism are illustrated at 2 and 4, the draft rolls at e and a, yam guide at In, and ring spinner with its traveller at l2. The feed roll supporting and driving means comprise a fixed supporting arm or bracket I4 carrying a bearing sleeve l6 within which a hollow shaft I 8 is rotatably mounted. The upper end of shaft I8 has a centrally apertured platform 20 secured thereto and the lower end of the shaft has a pair of bracket arms 22 fixedly secured thereto and a pair of arms 24 pivotally secured thereto; onlyone arm 22 and one arm 24 being visible in the drawing. Arms 22 rotatably support the shaftof feed roll 2 and arms 24 rotatably support the shaft of feed roll 4. Fixed to the lower end of sleeve I6 is an annular sun gear 26 which meshes with a. planet gear 28 carried on a shaft 30. Shaft 80, which is rotatably supported in a bearing sleeve 32 integral with the shaft I8, carries a worm 34 which meshes with, and drives, worm wheel 36 on the shaft of feed roll 2.

Platform is circular and is provided with radial teeth'38 on its "peripheryfor engagement with a pinion 40 carried on a drive shaft 42. In the particular embodiment of the invention two supply reels 44 of tow are rotatably mounted on the platform 20. The ends of the tow pass through the aperture in platform 20, through the hollow core of shaft l8 and between the feed rolls 2 and 4 into the ratch defined by the feed and draft rolls.

With the above described mechanism, rotation of the platform 20 by pinion 40 causes a slow rotation of the two rolls 2 and 4 as a unit about the axis of shaft 18 and causes planet gear 28 to rotate by travel around the fixed gear 26. Rotation of gear 28 through shaft 30, worm 34, and worm wheel 36 causes rotation of feed roll 2 about its axis with consequent feed of tow into the ratch. Thus a single drive means is provided for rotation of the feed roll assembly as a whole about one axis and for rotation of the individual feed rolls about their own axes. The twist of the sliver in the ratch occasioned by the rotation of the feed roll assembly is substantially concentrated near the draft rolls 6 and 8 because of the lower fiber density in this part of the ratch. Such concentration of twist strengthens the fiber where strength is needed as heretofore described and concentrates the fiber strand into a relatively narrow band at the entrance to the nips of the draft rolls.

A further advantage of the rotating assembly of the invention is in its use in combination with a wall in the ratch moving at the peripheral speed of the feed rolls, such as the endless belt 46 which passes around on idler roller 48 positioned high in the ratch and around the feed roll 8. In a copending application of the applicant, Serial Number 679,387, filed June 26, 1946, the improved operation of a direct tow to yarn spinner effected by the provision of such a moving wall in conjunction either with a cooperating trumpet or with a second similar moving wall, is disclosed and claimed. Briefly, such arrangement aids in smoothing and guiding the fibers in the ratch in their travel to the draft rolls, reduces wild ends in the beard, and results in the production of more uni-form yarn. Such moving wall, however, can only guide and confine those moving fibers that are engaged thereby. When the sliver in the ratch is twisted; as by the rotating feed roll assembly of the invention, the fibers on all sides of the beard are presented to the wall and hence such combination is more effective in smoothing and guiding the fibers in the ratch than two such belts or one belt and a trumpet.

The introduction of twist into the sliver in the ratch has an additional advantage where two or more ends of tow are to be drafted, as it insures a thorough mixing or blending of the tow from the different reels and this tends to counteract possible non-uniformity of the different ends.

In Fig. 2, an alternative arrangement for rotating the feed roll assembly is disclosed. In this embodiment of the invention a hollow shaft 50, which is mounted for rotation in a fixed bearing sleeve 52, carries at its lower end a relatively large external spur gear 53 which meshes with, and is driven by, the pinion gear 40 on drive shaft 42. A framework 54, carrying the driven feed roll 2 and idler feed roll 4 is mounted on the upper end of shaft 50 so as to rotate therewith. Rotation of feed roll 2 about its axis is effected, as in the construction of Fig. 1, through worm wheel 36 and worm 34 on shaft 30; shaft 30 being carried by the rotating framework 54. The specific means in Fig. 2 for rotating shaft 30 comprises a fixed internal spur gear 56 concentric with shaft 50 and spur gear 58 on shaft 30 which meshes with gear 56. A single supply reel 44a of tow is mounted on the framework 54 coaxially with shaft 50 and tow is led from the side thereof over the top of a centrally apertured disk 60 carried on the upper end of the reel and through the core of the reel to the nips of the feed rolls. In the particular embodiment of the invention illustrated in Fig. 2 a tube 62 of glass or the like which is secured to shaft 50 so as to rotate therewith extends to a point Just above the nips of the draft rolls 6 and 8, confines the sliver in the ratch, and twists the same by frictional engagement therewith. It will be understood that the moving belt 46 of. Fig. 1 could be used in Fig. 2 instead of the tube 82, and, for the spinning of particularly fine yarn, where the tube 62 is apt to introduce excessive friction, the moving belt is preferred.

The invention has now been described with reference to two embodiments thereof. Obviously variouschanges in the constructions illustrated could be made without departing from the spirit of the invention. For example, when a single end of tow is to be spun into yarn, the reel or pirn of tow need not be mounted on the rotating assembly, as a pretwist could be given the tow in a direction to prevent kinking of the tow during its passage to the feed rolls. When two or more ends of tow are to be spun, the supply reels or pirns should be rotatably mounted on the rotating feed roll assembly, as in Fig. 1, to avoid doubling of the tow before drafting. A platform for so rotatably supporting a plurality of supply reels could, of course, be provided in the construction of Fig. 2 if desired. Instead of rotating the feed roll assembly, twist could be imparted to the tow atan intermediate point in the ratch, or the draft roll assembly could be rotated to introduce the twist.

The degree of twist to be given the sliver in the ratch for optimum spinning of yarn will depend upon the denier of the tow, the length of ratch and the draft ratio of the mechanism but preferably is of the order of one turn for each two or three inches of tow in the ratch.

As a result of study and of experimentation with direct tow-to-yarn spinning mechanisms, certain criteria for eflicient spinning have been determined. For example, it is important that the ends in the ratch be directed downward with a smoothing action all the way to the nips of the draft rolls, and that the fibers be grouped into a small cross-section, say of a diameter of the order of one-sixteenth of an inch, at the entrance to the nips of the draft rolls. Twisting of the sliver in the ratch, as herein described effectively so groups the fibers at the nips of the feed rolls, and such twisting, in combination with the moving belt of Fig. 1, effectively directs and smooths the ends in the ratch in accordance with the first requirement.

Although, as above indicated, the invention is particularly adapted foruse in direct tow-toyarn spinning, it may be advantageously em- 5 played in either or both stages of a two-stage process, that is. in the conversion of tow to roving or in the conversion of roving to yarn or in both one of said draft rolls for guiding the material.

in its passage through the ratch.,

2. In a machine for stretch breaking tow, the

3. The process of converting tow to yarn which comprises doubling and twisting ends of tow while subyecting the ends to tension suilicient to stretch break the tow and draft the broken filaments thereof.

4. In a machine for converting filamentary textile material the combination comprising a pair of feed rolls and a pair of draft rolls defining a ratch therebetween for passage of the fila-- mentary material therethrough. a supporting structure for said feed rolls. supply reels for materials rotatably mounted on said structure,

combination comprising a pair of feed rolls for U passage of tow therebetween, a supporting structure therefor including a hollow shaft for passage of tow therethrough, said shaft extending at right angles to the plane passing \through the axes of said rolls and with its axis passing between said rolls, a fixed bearing sleeve for said shaft. drive means for rotating said shaft in said sleeve, a fixed gear, means carried by said structure and cooperating with said fixed gear for rotating one of said feed rolls about its axis in timed relation with the rotation of said structure and a platform carried by said structure and having an aperture therein aligned with the axis of said shaft, and means on said platform for rotatably supporting a plurality of supply reels of tow whereby a plurality of ends may be passed through said aperture and through the shaft to the feed rolls for blending and twisting by the rotation of said structure. 1

means for rotating said structure about an axis passing between the feed rolls and substantially perpendicular to the plane containing the axes of the feed rolls and means for rotating the feed and draft rolls about their axes whereby ends drawn from ,said reels by said feed rolls are twisted and doubled in the ratch.

NORMAN E. KLEIN.

nnrii'aamcss CITED The following references are of record in the file of this patent: UNITEDUSTATES PATENTS Number Name Date 647,138 Holmes et al. Apr. 10. 1900 1,596,804 Casablancas Aug. 17, 1926 1,922,949 Harris Aug. 15, 1933 2,256,436 Kruse Sept. 16, 1941 2,427,955 Fumess Sept. 23, 1947 2,432,355 Truitt Dec. 9, 1947 FOREIGN PATENTS Number Country Date 28,325 Great Britain of 1907 502,216 Germany Dec. 20, 1928 628,257 France Oct. 21, 1927 

